Preheat the oven to 375F. Line a 9-inch square baking dish with parchment paper. Grease the parchment with butter and sprinkle lightly with flour to coat. Tap the pan to discard the excess flour.

In a large mixing bowl, add the flour, sugar, baking powder, cinnamon, and salt and mix well to combine. Add the dates and nuts and stir to combine.

In a small bowl, with a whisk or a fork beat the eggs with 2 tablespoons of water and vanilla until combined. Pour the egg mixture into the bowl with the dry ingredients, and stir until to until smooth.

Pour the batter into the baking dish and smooth it into an even layer with a spatula. Bake until a toothpick inserted into the middle comes out clean, about 20-25 minutes.

Remove from the oven and let cool completely in the pan. Using the parchment, lift the cake onto a cutting board. Cut into 16 equal pieces and dust with confectioners’ sugar (optional). Leftover torta can be stored in an airtight container in the refrigerator for 5-7 days.